It protected young undocumented immigrants from deportation. Now Congress has six months to replace it.
Obama called Trump's move "cruel and wrong", but the Republican president said he is upholding the Constitution.
So, what does it mean for those who know no country other than the US? And is politics involved in this controversial decision?
Presenter: Hashem Ahelbarra
Rina Shah - Founder and principal of Rilax Strategies
Noor Zafar - Lawyer at the Center for Constitutional Rights
Joe Watkins - Republican political strategist
Watch on aljazeera.com.